The Claywater Meteorite explodes just before reaching ground level in Vernon County, Wisconsin; fragments having a combined mass of 1.5 kg (3.3 lb) are recovered.

American Civil War: In Virginia, Confederate forces capture Fort Stedman from the Union. Lee's army suffers heavy casualties: about 2,900, including 1,000 captured in the Union counterattack. Confederate positions are weakened. After the battle, Lee's defeat is only a matter of time.

April 15 – President Lincoln dies early this morning from his gunshot wound. Vice President Andrew Johnson becomes the 17th President of the United States, upon Lincoln's death. Johnson is sworn in later that morning.

September 26 – Champ Ferguson becomes the first person (and one of only two) to be convicted of war crimes for actions taken during the American Civil War, found guilty by a U.S. Army tribunal on 23 charges, arising from the murder of 53 people. He is hanged on October 20, two days after the conviction of Henry Wirz for war crimes.[8]